Some known packaging containers are formed by laminating a barrier layer (such as an aluminum foil, aluminum deposited film, or inorganic oxide deposited film) between a paper substrate layer and a sealant layer of thermoplastic resin, folding the sheet material into a box-like shape, and overlapping and sealing the edges of the sheet material (see PTL 1).
These packaging containers can take various forms. One such packaging container has a gable roof panel formed with a spout assembly and a cap which are made of polyethylene or the like so as to allow liquids inside the container to be poured out. When these packaging containers are disposed of, a container body made of a paper sheet material and a spout assembly welded to it should be separated from each other for separate collection. The container body and spout assembly can be separated by opening the top seal and cutting a sheet material around the spout assembly using scissors or the like. However, these packaging containers are usually hard to break down because the top seal is secure, and spout assemblies are often not separated from them.
PTL 2 discloses a paper package, which is a scored paper container having a spout assembly with an annular thin-walled portion formed on the inner upper surface of its annulus (flange). This paper package is folded along the scores, which causes the annular thin-walled portion to break, allowing a cylindrical section of the spout assembly to be separated from the paper container.